showAsDropDown

Display the content view in a popup window anchored to the bottom-left
corner of the anchor view offset by the specified x and y coordinates.
If there is not enough room on screen to show
the popup in its entirety, this method tries to find a parent scroll
view to scroll. If no parent scroll view can be scrolled, the bottom-left
corner of the popup is pinned at the top left corner of the anchor view.

If the view later scrolls to move anchor to a different
location, the popup will be moved correspondingly.